# makefile to build tests for merge sort

CXX = g++
AR = ar
ARFLAGS = -rv

# Points to the root of Google Test, relative to where this file is.
GTEST_DIR = ../../gtest

# Flags passed to the preprocessor.
CPPFLAGS += -I$(GTEST_DIR)/include

# Flags passed to the C++ compiler.
CXXFLAGS += -g -Wall -Wextra

# All tests produced by this Makefile.
TESTS = mergesort_test

# All Google Test headers.  Usually you shouldn't change this
# definition.
GTEST_HEADERS = $(GTEST_DIR)/include/gtest/*.h \
                $(GTEST_DIR)/include/gtest/internal/*.h


# House-keeping build targets.

all : $(TESTS)

clean : 
	rm -f $(TESTS) gtest.a gtest_main.a *.o

# Builds gtest.a and gtest_main.a.

# Usually you shouldn't tweak such internal variables, indicated by a
# trailing _.
GTEST_SRCS_ = $(GTEST_DIR)/src/*.cc $(GTEST_DIR)/src/*.h $(GTEST_HEADERS)

# For simplicity and to avoid depending on Google Test's
# implementation details, the dependencies specified below are
# conservative and not optimized.  This is fine as Google Test
# compiles fast and for ordinary users its source rarely changes.
gtest-all.o : $(GTEST_SRCS_)
	$(CXX) $(CPPFLAGS) -I$(GTEST_DIR) $(CXXFLAGS) -c \
            $(GTEST_DIR)/src/gtest-all.cc

gtest_main.o : $(GTEST_SRCS_)
	$(CXX) $(CPPFLAGS) -I$(GTEST_DIR) $(CXXFLAGS) -c \
            $(GTEST_DIR)/src/gtest_main.cc

# gtest lib
gtest.a : gtest-all.o
	$(AR) $(ARFLAGS) $@ $^

# entry point to run gtest
gtest_main.a : gtest-all.o gtest_main.o
	$(AR) $(ARFLAGS) $@ $^

# Builds a sample test.  A test should link with either gtest.a or
# gtest_main.a, depending on whether it defines its own main()
# function.

mergesort_test.o : mergesort_test.cc mergesort.h mergesort_soln.h $(GTEST_HEADERS)
	$(CXX) $(CPPFLAGS) $(CXXFLAGS) -c mergesort_test.cc

mergesort_test : mergesort_test.o gtest_main.a
	$(CXX) $(CPPFLAGS) $(CXXFLAGS) -pthread $^ -o $@
